This invention relates generally to power transmissions employing axially shiftable planetary gear sets and more specifically to shift inhibitors therefor.
Simple planetary transmissions such as are employed in four wheel drive transfer cases and which provide means for effecting gear ratio changes by selectively axially shifting elements of the planetary gear set are well known in the art. Exemplary of such transmissions is that shown in U.S. Pat. No. 4,103,753.
Since the limited purpose for which such transmissions are used in multi-ratio applications has not justified design of a complex, expensive synchronized gear shifting, care must be taken in their use to avoid shifting at high speeds to avoid damage to gear components.